The present invention relates to an apparatus for screening a suspension of fibrous cellulose pulp, comprising an elongate housing and a rotor shaft extending therethrough.
Screening apparatuses for screening pulps are known through, for instance, U.S. Pat. Nos. 4,680,108 and 817,333. However, the screening apparatus disclosed in U.S. Pat. No. 4,680,108 includes two screening sections which are located close to each other and the intention is to extract two different accepts from the screening apparatus. The apparatus described in U.S. Pat. No. 817,333 consists of two parts spaced from each other, each having a cylindrical casing or housing. Again, the intention is to extract and discharge an accept from each part of the apparatus, the reject or tailings from the first part being used as inject in the second part.
In order to screen an accept from a screening apparatus once again, or a further number of times, a plurality of separate screening apparatuses have hitherto been used, disposed one after the other and driven individually. Such an installation is expensive, requires considerable space and the power consumption is high. Furthermore, the instrumentation required for flow-measurement is relatively extensive.